Roller carriages of this kind, in which the securing device is embodied as a blocking element clampable against the guidance and runner rail, are known from practical use. This blocking element can be embodied as a screw that can either be pressed, by rotation, against the guidance and runner rail, or can be at a distance from it. A disadvantage in this context is that extended retention of the open roof is necessary until sufficiently clamping has been produced. In addition, accessibility is often limited and, with insufficient actuation and thus insufficient clamping, displacements can result in scraping on the guidance and runner rail and thus in damage to the guidance and runner rail.
These problems can also occur with blocking elements that, by way of a pivoting lever or push bar, press a rubber element onto the guidance and runner rail. Such blocking elements are furthermore subject to a bending load when used as intended, and functional impairments can occur as a result of wear on the rubber element.
Also known are blocking elements that are slid into a corresponding recess or bore of the guidance and runner rail and thus achieve positively engaged securing of the roller carriage. A disadvantage in this context is that another bore is required for each position, thereby weakening the guidance and runner rail. In addition, damage to the rollers can be caused by the bores because of sharp edges, and roller running can be interfered with.